A new method to measure the accuracy of intraoral scanners along the complete dental arch: A pilot study

Abstract

PURPOSEThe purpose of this study is to assess the accuracy of three intraoral scanners along the complete dental arch and evaluate the feasibility of the assessment methodology for further in vivo analysis.MATERIALS AND METHODSA specific measurement pattern was fabricated and measured using a coordinate measuring machine for the assessment of control distances and angles. Afterwards, the pattern was placed and fixed in replica of an upper jaw for their subsequent scans (10 times) using 3 intraoral scanners, namely iTero Element1, Trios 3, and True Definition. 4 reference distances and 5 angles were measured and compared with the controls. Trueness and precision were assessed for each IOS: trueness, as the deviation of the measures from the control ones, while precision, as the dispersion of measurements in each reference parameter. These measurements were carried out using software for analyzing 3-dimensional data. Data analysis software was used for statistical and measurements analysis (α=.05).RESULTSSignificant differences (P<.05) were found depending on the intraoral scanner used. Best trueness values were achieved with iTero Element1 (mean from 10 ± 7 µm to 91 ± 63 µm) while the worst values were obtained with Trios3 (mean from 42 ± 23 µm to 174 ± 77 µm). Trueness analysis in angle measurements, as well as precision analysis, did not show conclusive results.CONCLUSIONiTero Element1 was more accurate than the current versions of Trios3 and True Definition. Importantly, the proposed methodology is considered reliable for analyzing accuracy in any dental arch length and valid for assessing both trueness and precision in an in vivo study.

Accuracy of Digital and Conventional Full-Arch Impressions in Patients: An Update

“…These findings are comparable with previous investigations [3,10]. However, the total deviations for the Trios 3 Pod and the Primescan in this clinical study were higher compared with the laboratory data reported by Ender et al [9] and Iturrate et al [33]. This could be due to different evaluation methods (percentiles) and furthermore explained by the in vivo conditions and the presence of saliva, oral structures, and patient movement(s) that may influence accuracy [34][35][36].…”

The direct digital workflow in fixed implant prosthodontics: a narrative review

“…Mizumoto et al [ 75 ] in a recent in vitro study have reported that in the completely edentulous maxilla with 4 installed implants, including scanning data from the palate did not result in statistically significant higher accuracy. In an effort to minimize discrepancies when scanning edentulous sites among multiple implants, Iturrate et al [ 76 , 77 ] have investigated the in vitro effectiveness of using an auxiliary geometric device (AGD) firmly attached onto the implant scanbodies. The authors reported statistically significantly higher accuracy when the AGD was used regardless of the IOS scanner tested.…”

Trueness of 12 intraoral scanners in the full-arch implant impression: a comparative in vitro study

“…Because it is not possible to use machines with certified accuracy such as CMMs, articulated arms or industrial scanners in the patient’s mouth, and having a certified reference file is not possible, measuring the trueness of optical impressions with IOS in vivo is difficult [ 2 , 4 , 18 ]. Some authors have recently tried to introduce indexes [ 19 , 20 ] or geometric shapes with known dimensions (custom measuring aids) [ 21 , 22 ] in the mouth to evaluate the distortions affecting the optical impression in vivo, but the vast majority of studies of the trueness of IOSs have been made in vitro on plaster models [ 14 , 15 , 23 – 26 ].…”